POSIX: use lockstep_scheduler to fake time

This integrates the lockstep_scheduler, so that the system time is set
by the mavlink HIL_SENSOR message.

This means that the speed factor is removed and the speed is entirely
given by the simulator.
This commit is contained in:
Julian Oes 2018-10-15 15:00:29 +02:00
parent f0ce300744
commit 3e6e1f5c2b
5 changed files with 74 additions and 125 deletions

View File

@ -43,14 +43,13 @@
#include <px4_workqueue.h>
#include <px4_tasks.h>
#include <drivers/drv_hrt.h>
#include <lockstep_scheduler/lockstep_scheduler.h>
#include <semaphore.h>
#include <time.h>
#include <string.h>
#include <inttypes.h>
#include <errno.h>
#include "hrt_work.h"
#define SPEED_FACTOR 1
static struct sq_queue_s callout_queue;
@ -73,6 +72,8 @@ static hrt_abstime _delay_interval = 0;
static hrt_abstime max_time = 0;
pthread_mutex_t _hrt_mutex = PTHREAD_MUTEX_INITIALIZER;
static LockstepScheduler lockstep_scheduler;
static void
hrt_call_invoke(void);
@ -81,6 +82,12 @@ _hrt_absolute_time_internal(void);
__EXPORT hrt_abstime hrt_reset(void);
hrt_abstime hrt_absolute_time_offset(void)
{
return px4_timestart_monotonic;
}
static void hrt_lock(void)
{
px4_sem_wait(&_hrt_lock);
@ -191,7 +198,7 @@ hrt_abstime hrt_absolute_time(void)
return ret;
}
__EXPORT hrt_abstime hrt_reset(void)
hrt_abstime hrt_reset(void)
{
#ifndef __PX4_QURT
px4_timestart_monotonic = 0;
@ -203,7 +210,7 @@ __EXPORT hrt_abstime hrt_reset(void)
/*
* Convert a timespec to absolute time.
*/
hrt_abstime ts_to_abstime(struct timespec *ts)
hrt_abstime ts_to_abstime(const struct timespec *ts)
{
hrt_abstime result;
@ -594,61 +601,62 @@ int px4_clock_gettime(clockid_t clk_id, struct timespec *tp)
// Don't do any offseting on the Linux side on the Snapdragon.
return clock_gettime(clk_id, &tp);
#else
struct timespec actual_tp;
const int ret = clock_gettime(clk_id, &actual_tp);
if (ret != 0) {
return ret;
}
const uint64_t actual_usec = ts_to_abstime(&actual_tp);
if (clk_id == CLOCK_MONOTONIC) {
if (px4_timestart_monotonic == 0) {
px4_timestart_monotonic = actual_usec;
}
abstime_to_ts(tp, (actual_usec - px4_timestart_monotonic) * SPEED_FACTOR);
const uint64_t abstime = lockstep_scheduler.get_absolute_time();
abstime_to_ts(tp, abstime - px4_timestart_monotonic);
return 0;
} else {
abstime_to_ts(tp, actual_usec);
return system_clock_gettime(clk_id, tp);
}
//static unsigned counter = 0;
//if (counter++ % 1000000 == 0) {
// PX4_INFO("clk_id: %d, actual_tp.tv_sec: %llu, actual_tp.tv_nsec: %llu, px4_timestart: %llu: 0x%x",
// clk_id, actual_tp.tv_sec, actual_tp.tv_nsec, px4_timestart[clk_id], &px4_timestart[clk_id]);
//}
return 0;
#endif
}
int px4_clock_settime(clockid_t clk_id, const struct timespec *tp)
int px4_clock_settime(clockid_t clk_id, const struct timespec *ts)
{
// not implemented
return 0;
if (clk_id == CLOCK_REALTIME) {
return system_clock_settime(clk_id, ts);
} else {
const uint64_t time_us = ts_to_abstime(ts);
if (px4_timestart_monotonic == 0) {
px4_timestart_monotonic = time_us;
}
lockstep_scheduler.set_absolute_time(time_us);
return 0;
}
}
int px4_usleep(useconds_t usec)
{
return system_usleep(usec / SPEED_FACTOR);
if (px4_timestart_monotonic == 0) {
// Until the time is set by the simulator, we fallback to the normal
// usleep;
return system_usleep(usec);
}
const uint64_t time_finished = lockstep_scheduler.get_absolute_time() + usec;
return lockstep_scheduler.usleep_until(time_finished);
}
unsigned int px4_sleep(unsigned int seconds)
{
useconds_t usec = seconds * 1000000;
return system_usleep(usec / SPEED_FACTOR);
return px4_usleep(usec);
}
int px4_pthread_cond_timedwait(pthread_cond_t *cond,
pthread_mutex_t *mutex,
const struct timespec *abstime)
const struct timespec *ts)
{
struct timespec new_abstime;
new_abstime.tv_sec = abstime->tv_sec / SPEED_FACTOR;
new_abstime.tv_nsec = abstime->tv_nsec / SPEED_FACTOR;
return pthread_cond_timedwait(cond, mutex, &new_abstime);
const uint64_t time_us = ts_to_abstime(ts);
const uint64_t scheduled = time_us + px4_timestart_monotonic;
return lockstep_scheduler.cond_timedwait(cond, mutex, scheduled);
}

View File

@ -85,7 +85,7 @@ __EXPORT extern hrt_abstime hrt_absolute_time(void);
/**
* Convert a timespec to absolute time.
*/
__EXPORT extern hrt_abstime ts_to_abstime(struct timespec *ts);
__EXPORT extern hrt_abstime ts_to_abstime(const struct timespec *ts);
/**
* Convert absolute time to a timespec.
@ -191,6 +191,11 @@ __EXPORT extern void hrt_stop_delay(void);
*/
__EXPORT extern void hrt_stop_delay_delta(hrt_abstime delta);
__EXPORT extern hrt_abstime hrt_reset(void);
__EXPORT extern hrt_abstime hrt_absolute_time_offset(void);
#endif
__END_DECLS

View File

@ -97,6 +97,7 @@
// We don't poison usleep and sleep on NuttX because it is used in dependencies
// like uavcan and we don't need to fake time on the real system.
#include <unistd.h>
#include <time.h>
#define system_usleep usleep
#define system_sleep sleep

View File

@ -384,19 +384,19 @@ extern "C" {
// Get the current time
struct timespec ts;
// FIXME: check if QURT should probably be using CLOCK_MONOTONIC
px4_clock_gettime(CLOCK_REALTIME, &ts);
// px4_sem_timedwait is implemented using CLOCK_MONOTONIC.
px4_clock_gettime(CLOCK_MONOTONIC, &ts);
// Calculate an absolute time in the future
const unsigned billion = (1000 * 1000 * 1000);
unsigned tdiff = timeout;
uint64_t nsecs = ts.tv_nsec + (tdiff * 1000 * 1000);
uint64_t nsecs = ts.tv_nsec + (timeout * 1000 * 1000);
ts.tv_sec += nsecs / billion;
nsecs -= (nsecs / billion) * billion;
ts.tv_nsec = nsecs;
// Execute a blocking wait for that time in the future
errno = 0;
ret = px4_sem_timedwait(&sem, &ts);
#ifndef __PX4_DARWIN
ret = errno;

View File

@ -49,8 +49,6 @@
#include <limits>
extern "C" __EXPORT hrt_abstime hrt_reset(void);
#define SEND_INTERVAL 20
#define UDP_PORT 14560
@ -79,7 +77,7 @@ using namespace simulator;
void Simulator::pack_actuator_message(mavlink_hil_actuator_controls_t &msg, unsigned index)
{
msg.time_usec = hrt_absolute_time();
msg.time_usec = hrt_absolute_time() + hrt_absolute_time_offset();
bool armed = (_vehicle_status.arming_state == vehicle_status_s::ARMING_STATE_ARMED);
@ -286,69 +284,27 @@ void Simulator::handle_message(mavlink_message_t *msg, bool publish)
mavlink_hil_sensor_t imu;
mavlink_msg_hil_sensor_decode(msg, &imu);
bool compensation_enabled = (imu.time_usec > 0);
// set temperature to a decent value
imu.temperature = 32.0f;
struct timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts);
// uint64_t host_time = ts_to_abstime(&ts);
abstime_to_ts(&ts, imu.time_usec);
px4_clock_settime(CLOCK_MONOTONIC, &ts);
hrt_abstime curr_sitl_time = hrt_absolute_time();
hrt_abstime curr_sim_time = imu.time_usec;
hrt_abstime now_us = hrt_absolute_time();
if (compensation_enabled && _initialized
&& _last_sim_timestamp > 0 && _last_sitl_timestamp > 0
&& _last_sitl_timestamp < curr_sitl_time
&& _last_sim_timestamp < curr_sim_time) {
#if 0
// This is just for to debug missing HIL_SENSOR messages.
static hrt_abstime last_time = 0;
hrt_abstime diff = now_us - last_time;
float step = diff / 4000.0f;
px4_clock_gettime(CLOCK_MONOTONIC, &ts);
uint64_t timestamp = ts_to_abstime(&ts);
perf_set_elapsed(_perf_sim_delay, timestamp - curr_sim_time);
perf_count(_perf_sim_interval);
int64_t dt_sitl = curr_sitl_time - _last_sitl_timestamp;
int64_t dt_sim = curr_sim_time - _last_sim_timestamp;
double curr_factor = ((double)dt_sim / (double)dt_sitl);
if (curr_factor < 5.0) {
_realtime_factor = _realtime_factor * 0.99 + 0.01 * curr_factor;
}
// calculate how much the system needs to be delayed
int64_t sysdelay = dt_sitl - dt_sim;
unsigned min_delay = 200;
if (dt_sitl < 1e5
&& dt_sim < 1e5
&& sysdelay > min_delay + 100) {
// the correct delay is exactly the scale between
// the last two intervals
px4_sim_start_delay();
hrt_start_delay();
unsigned exact_delay = sysdelay / _realtime_factor;
unsigned usleep_delay = (sysdelay - min_delay) / _realtime_factor;
// extend by the realtime factor to avoid drift
px4_usleep(usleep_delay);
hrt_stop_delay_delta(exact_delay);
px4_sim_stop_delay();
}
if (step > 1.1f || step < 0.9f) {
PX4_INFO("diff: %llu, step: %.2f", diff, step);
}
hrt_abstime now = hrt_absolute_time();
_last_sitl_timestamp = curr_sitl_time;
_last_sim_timestamp = curr_sim_time;
// correct timestamp
imu.time_usec = now;
last_time = now_us;
#endif
if (publish) {
publish_sensor_topics(&imu);
@ -363,21 +319,23 @@ void Simulator::handle_message(mavlink_message_t *msg, bool publish)
bool armed = (_vehicle_status.arming_state == vehicle_status_s::ARMING_STATE_ARMED);
if (!armed || batt_sim_start == 0 || batt_sim_start > now) {
batt_sim_start = now;
if (!armed || batt_sim_start == 0 || batt_sim_start > now_us) {
batt_sim_start = now_us;
}
float ibatt = -1.0f; // no current sensor in simulation
const float minimum_percentage = 0.5f; // change this value if you want to simulate low battery reaction
/* Simulate the voltage of a linearly draining battery but stop at the minimum percentage */
float battery_percentage = (now - batt_sim_start) / discharge_interval_us;
float battery_percentage = 1.0f - (now_us - batt_sim_start) / discharge_interval_us;
battery_percentage = math::min(battery_percentage, minimum_percentage);
float vbatt = math::gradual(battery_percentage, 0.f, 1.f, _battery.full_cell_voltage(), _battery.empty_cell_voltage());
vbatt *= _battery.cell_count();
const float throttle = 0.0f; // simulate no throttle compensation to make the estimate predictable
_battery.updateBatteryStatus(now, vbatt, ibatt, true, true, 0, throttle, armed, &_battery_status);
_battery.updateBatteryStatus(now_us, vbatt, ibatt, true, true, 0, throttle, armed, &_battery_status);
// publish the battery voltage
int batt_multi;
@ -734,17 +692,12 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
PX4_INFO("Waiting for initial data on UDP port %i. Please start the flight simulator to proceed..", udp_port);
fflush(stdout);
uint64_t pstart_time = 0;
bool no_sim_data = true;
while (!px4_exit_requested() && no_sim_data) {
pret = ::poll(&fds[0], fd_count, 100);
if (fds[0].revents & POLLIN) {
if (pstart_time == 0) {
pstart_time = hrt_system_time();
}
len = recvfrom(_fd, _buf, sizeof(_buf), 0, (struct sockaddr *)&_srcaddr, &_addrlen);
// send hearbeat
@ -764,7 +717,7 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
// have a message, handle it
handle_message(&msg, publish);
if (msg.msgid != 0 && (hrt_system_time() - pstart_time > 1000000)) {
if (msg.msgid != 0) {
PX4_INFO("Got initial simulation data, running sim..");
no_sim_data = false;
}
@ -778,9 +731,6 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
return;
}
// reset system time
(void)hrt_reset();
// subscribe to topics
for (unsigned i = 0; i < (sizeof(_actuator_outputs_sub) / sizeof(_actuator_outputs_sub[0])); i++) {
_actuator_outputs_sub[i] = orb_subscribe_multi(ORB_ID(actuator_outputs), i);
@ -794,8 +744,6 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
mavlink_status_t udp_status = {};
bool sim_delay = false;
const unsigned max_wait_ms = 4;
//send MAV_CMD_SET_MESSAGE_INTERVAL for HIL_STATE_QUATERNION ground truth
@ -817,23 +765,10 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
//timed out
if (pret == 0) {
if (!sim_delay) {
// we do not want to spam the console by default
// PX4_WARN("mavlink sim timeout for %d ms", max_wait_ms);
sim_delay = true;
px4_sim_start_delay();
hrt_start_delay();
}
continue;
}
if (sim_delay) {
sim_delay = false;
hrt_stop_delay();
px4_sim_stop_delay();
}
// this is undesirable but not much we can do
if (pret < 0) {
PX4_WARN("simulator mavlink: poll error %d, %d", pret, errno);